Tutorial – A tutorial for Mail_Queue

Mail_Queue usage with a simple example

We are using the db-container for the example and a mysql database. You need to create some tables in the mysql-database to store the messages:


CREATE TABLE mail_queue (
  id bigint(20) NOT NULL default '0',
  create_time datetime NOT NULL default '0000-00-00 00:00:00',
  time_to_send datetime NOT NULL default '0000-00-00 00:00:00',
  sent_time datetime default NULL,
  id_user bigint(20) NOT NULL default '0',
  ip varchar(20) NOT NULL default 'unknown',
  sender varchar(50) NOT NULL default '',
  recipient text NOT NULL,
  headers text NOT NULL,
  body longtext NOT NULL,
  try_sent tinyint(4) NOT NULL default '0',
  delete_after_send tinyint(1) NOT NULL default '1',
  PRIMARY KEY  (id),
  KEY id (id),
  KEY time_to_send (time_to_send),
  KEY id_user (id_user)

First you need to define some options. As you need them two times (once for adding messages, once for sending the messages) its always good to add them to a config-file. Let's call it config.php



require_once "Mail/Queue.php";

// options for storing the messages
// type is the container used, currently there are 'creole', 'db', 'mdb' and 'mdb2' available
$db_options['type']       = 'mdb2';
// the others are the options for the used container
// here are some for db
$db_options['dsn']        = 'mysql://user:password@host/database';
$db_options['mail_table'] = 'mail_queue';

// here are the options for sending the messages themselves
// these are the options needed for the Mail-Class, especially used for Mail::factory()
$mail_options['driver']    = 'smtp';
$mail_options['host']      = 'your_server_smtp.com';
$mail_options['port']      = 25;
$mail_options['localhost'] = 'localhost'//optional Mail_smtp parameter
$mail_options['auth']      = false;
$mail_options['username']  = '';
$mail_options['password']  = '';


So we are done configuring it, now let's use it. First we need to construct a mail-message and add it to the queue:


include './config.php';
/* we use the db_options and mail_options here */
$mail_queue =& new Mail_Queue($db_options$mail_options);

$from 'user@server.com';
$to "user2@server.com";
$message 'Hi! This is test message!! :)';

$hdrs = array( 'From'    => $from,
'To'      => $to,
'Subject' => "test message body"  );

/* we use Mail_mime() to construct a valid mail */
$mime =& new Mail_mime();
$body $mime->get();
// the 2nd parameter allows the header to be overwritten
// @see http://pear.php.net/bugs/18256
$hdrs $mime->headers($hdrstrue); 

/* Put message to queue */


NB: the first time you call put(), PEAR::DB and PEAR::MDB2 will create a new table to keep the sequence number, so make sure the db user you are using has "CREATE TABLE" privileges. Or you can create the table separately, calling the createSequence() method of PEAR::DB or PEAR::MDB2 (you should also be aware that the two DBAL will create a table with a different field name: "id" for DB, "sequence" for MDB2).

Ok, now we've used the simple way to add a message ... there are more advanced options, please check docs of the put-function for these. Now we need to send the messages. This is most often done by using a cron-job which regularly runs a script to send the messages. Here is a simple script to achieve this:


include './config.php';

/* How many mails could we send each time the script is called */
$max_amount_mails 50;

/* we use the db_options and mail_options from the config again  */
$mail_queue =& new Mail_Queue($db_options$mail_options);

/* really sending the messages */

We are done. Now run the last script regularly and add your mails to the queue as needed.

Since Mail_Queue v.1.1, the preload() method doesn't preload ALL the mails in memory, but just a few of them each time. When the buffer is empty, it is filled again automatically. You can set the size of the buffer via the new setBufferSize() method.

You can also send the stored emails one by one. Here is a simple script to achieve this:


// set the internal buffer size according your
// memory resources (the number indicates how
// many emails can stay in the buffer at any
// given time)


//set the queue size (i.e. the number of mails to send)
$limit 50;

// loop through the stored emails and send them
while ($mail $mail_queue->get()) {
$result $mail_queue->sendMail($mail);

Utilising Callbacks for Report Generation

The sendMailsInQueue method, since version 1.2.3, has callback support. This may be utilised for report generation and postprocessing.

The callback function is called before the relevant entry is deleted from the mail_queue table in the database so if necessary you could add extra fields to it for inserting into your log/report table. The function should accept only one parameter - an associative array of values; 'id', 'queued_as' and 'greeting'.

You'll need to use recent releases of the PEAR::Mail (version 1.2.0b3 or higher) and PEAR::Net_SMTP (version 1.3.3 or higher) packages to be able to retrieve the esmtp id and greeting details if you need them for your reports. Also, if you want to decode the body of the email and store that for your report you'll need to install the PEAR::Mail_mimeDecode package.

Provide the callback function like so:


mailqueue_callback($args) {
$row get_mail_queue_row($args['id']);
$headers unserialize($row['headers']);
$subject $headers['Subject'];
$body unserialize($row['body']);

$mail_headers '';
$headers as $key=>$value) {
$mail_headers .= "$key:$value\n";
$mail $mail_headers "\n" $body;
$decoder = new Mail_mimeDecode($mail);
$decoded $decoder->decode(array(
'include_bodies' => TRUE,
'decode_bodies'  => TRUE,
'decode_headers'  => TRUE,
$body $decoded->body;

$esmtp_id $args['queued_as'];
    if (isset(
$args['greeting'])) {
$greeting $args['greeting'];
$greets explode(' '$greeting);
$server $greets[0];
    } else {
$server 'localhost';


Mail_Queue - base class for mail queue managment. (Previous) Mail_Queue constructor (Next)
Last updated: Sat, 16 Feb 2019 — Download Documentation
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User Notes:

Note by: santiago@vuelocreativo.com
Where´s the function get_mail_queue_row???
Note by: tbauserman@clickedstudios.com
In the example for send_message.php It doesn't delete the message from the queue. With the example it would keep sending the queued messages over and over again. I had to add change the sendMail function in Queue.php
from this
if (!PEAR::isError($sent) && $sent && $set_as_sent) {

to this
if (!PEAR::isError($sent) && $sent && $set_as_sent) {
if($mail->isDeleteAfterSend()) {
Note by: kguest
the mime encoding of the attachments plus message and ancillary data stored in the mailbody may push the size of required storage of that which might be used for the raw data that you may be storing elsewhere in the database.

in other words - always make sure the fields in your database are
[more than] large enough for the data going in: if you are storing raw data in a blob and mail_queue is not delivering the constructed mails properly, perhaps you should use a longblob as the datatype for the body field in the mail_queue table.